In a cryogenic tank including a concrete wall, in order to prevent permeation of water from the outside, a metal vapor barrier having higher airtightness than a resin vapor barrier may be provided to abut the inner wall surface of the concrete wall. The vapor barrier is formed by welding a plurality of panels.
Japanese Unexamined Patent Application, Second Publication No. S62-033477 and Japanese Unexamined Patent Application, Second Publication No. H04-080280 are examples of the related art.